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Shen Y, Hussey NE, David M, Wu F, Li Y. Vertebral microchemistry as an indicator of habitat use of the oceanic whitetip shark Carcharhinus longimanus in the central and eastern Pacific Ocean. JOURNAL OF FISH BIOLOGY 2024; 104:1732-1742. [PMID: 38445757 DOI: 10.1111/jfb.15705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 02/13/2024] [Indexed: 03/07/2024]
Abstract
The oceanic whitetip shark, Carcharhinus longimanus, is a highly migratory, epipelagic top predator that is classified as critically endangered. Although this species is widely distributed throughout the world's tropical oceans, its assumed mobility and pelagic behavior limit studies to derive required lifetime data for management. To address this data deficiency, we assessed variation in the habitat use of C. longimanus by oceanic region and over ontogeny through time series trace element and stable isotope values conserved along the vertebral centra (within translucent annulus bands) of 13 individuals sampled from the central and eastern Pacific Ocean. Elemental ratios of Mg:Ca, Mn:Ca, Fe:Ca, Zn:Ca, and Ba:Ca varied significantly among individuals from both sampling regions while principal component analysis of combined standardized elements revealed minimal overlap between the two areas. The limited overlap was also in agreement with stable isotope niches. These findings indicate that C. longimanus exhibit a degree of fidelity to sampling regions but also connectivity in a proportion of the population. The relatively stable Sr:Ca ratio supports its occurrence in oceanic environments. The decreasing trends in Ba:Ca, Mn:Ca, and Zn:Ca ratios, as well as in carbon and nitrogen isotope values along vertebral transects, indicate that C. longimanus undergo a directional habitat shift with age. Combined elemental and stable isotope values in vertebral centra provide a promising tool for elucidating lifetime data for complex pelagic species. For C. longimanus, management will need to consider subpopulation movement behavior in the Pacific to minimize the potential for localized depletions. Further work is now required to sample individuals across the entire Pacific and to link these findings with genetic and movement data to define population structure.
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Affiliation(s)
- Yongfu Shen
- College of Marine Living Resources and Management, Shanghai Ocean University, Shanghai, China
| | - Nigel E Hussey
- Department of Integrative Biology, University of Windsor, Windsor, Ontario, Canada
| | - Mboglen David
- College of Marine Living Resources and Management, Shanghai Ocean University, Shanghai, China
| | - Feng Wu
- College of Marine Living Resources and Management, Shanghai Ocean University, Shanghai, China
- The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China
- National Engineering Research Centre for Oceanic Fisheries, Shanghai Ocean University, Shanghai, China
| | - Yunkai Li
- College of Marine Living Resources and Management, Shanghai Ocean University, Shanghai, China
- The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China
- National Engineering Research Centre for Oceanic Fisheries, Shanghai Ocean University, Shanghai, China
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Blanluet A, Game ET, Dunn DC, Everett JD, Lombard AT, Richardson AJ. Evaluating ecological benefits of oceanic protected areas. Trends Ecol Evol 2024; 39:175-187. [PMID: 37778906 DOI: 10.1016/j.tree.2023.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/31/2023] [Accepted: 09/01/2023] [Indexed: 10/03/2023]
Abstract
Oceans beyond the continental shelf represent the largest yet least protected environments. The new agreement to increase protection targets to 30% by 2030 and the recent United Nations (UN) High Seas Treaty try to address this gap, and an increase in the declaration of oceanic Marine Protected Areas (oMPAs) in waters beyond 200 m in depth is likely. Here we find that there is contradictory evidence concerning the benefits of oMPAs in terms of protecting pelagic habitats, providing refuge for highly mobile species, and potential fisheries benefits. We discover a mismatch between oMPA management objectives focusing on protection of pelagic habitats and biodiversity, and scientific research focusing on fisheries benefits. We suggest that the solution is to harness emerging technologies to monitor inside and outside oMPAs.
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Affiliation(s)
- Arthur Blanluet
- School of the Environment, The University of Queensland, St Lucia, QLD, 4072, Australia; The Nature Conservancy, South Brisbane, Queensland 4101, Australia.
| | - Edward T Game
- The Nature Conservancy, South Brisbane, Queensland 4101, Australia
| | - Daniel C Dunn
- School of the Environment, The University of Queensland, St Lucia, QLD, 4072, Australia; Centre for Biodiversity and Conservation Science (CBCS), The University of Queensland, St Lucia, 4072, QLD, Australia
| | - Jason D Everett
- School of the Environment, The University of Queensland, St Lucia, QLD, 4072, Australia; Commonwealth Scientific and Industrial Research Organization (CSIRO) Environment, Queensland Biosciences Precinct (QBP), St Lucia, QLD 4067, Australia; Centre for Marine Science and Innovation, University of New South Wales, Sydney, NSW, Australia
| | - Amanda T Lombard
- Institute for Coastal and Marine Research, Nelson Mandela University, Gqeberha, South Africa
| | - Anthony J Richardson
- School of the Environment, The University of Queensland, St Lucia, QLD, 4072, Australia; Centre for Biodiversity and Conservation Science (CBCS), The University of Queensland, St Lucia, 4072, QLD, Australia; Commonwealth Scientific and Industrial Research Organization (CSIRO) Environment, Queensland Biosciences Precinct (QBP), St Lucia, QLD 4067, Australia
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Measuring the Impact of Conservation: The Growing Importance of Monitoring Fauna, Flora and Funga. DIVERSITY 2022. [DOI: 10.3390/d14100824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Many stakeholders, from governments to civil society to businesses, lack the data they need to make informed decisions on biodiversity, jeopardising efforts to conserve, restore and sustainably manage nature. Here we review the importance of enhancing biodiversity monitoring, assess the challenges involved and identify potential solutions. Capacity for biodiversity monitoring needs to be enhanced urgently, especially in poorer, high-biodiversity countries where data gaps are disproportionately high. Modern tools and technologies, including remote sensing, bioacoustics and environmental DNA, should be used at larger scales to fill taxonomic and geographic data gaps, especially in the tropics, in marine and freshwater biomes, and for plants, fungi and invertebrates. Stakeholders need to follow best monitoring practices, adopting appropriate indicators and using counterfactual approaches to measure and attribute outcomes and impacts. Data should be made openly and freely available. Companies need to invest in collecting the data required to enhance sustainability in their operations and supply chains. With governments soon to commit to the post-2020 global biodiversity framework, the time is right to make a concerted push on monitoring. However, action at scale is needed now if we are to enhance results-based management adequately to conserve the biodiversity and ecosystem services we all depend on.
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Philopatry as a Tool to Define Tentative Closed Migration Cycles and Conservation Areas for Large Pelagic Fishes in the Pacific. SUSTAINABILITY 2022. [DOI: 10.3390/su14095577] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Migrations of large pelagic fishes across the Pacific are usually inferred from tagging or genetic studies. Even though these techniques have improved over time, they still fail to demonstrate large transoceanic migrations, usually proposing ‘routes’ that do not cycle seasonally. The current study uses the concept of ‘philopatry’ in 11 large pelagic fish species, i.e., the tendency for animals to return to their natal site to reproduce. Tentative migration routes and maps emerge by applying this concept to the movements extracted through a comprehensive review of the literature on satellite and conventional tagging, and population and subpopulation linkages inferred from genetic and/or genomic studies. Moreover, when comparing these proposed migration routes and the mapped reconstructed catch (1950–2016, Sea Around Us) of each species in the Pacific, similarities emerge, reinforcing the accuracy of these migration cycles informed by philopatry. Finally, by superposing the migration routes of our 11 species, we identified areas of the Pacific that are part of the inferred migration routes of multiple species, leading to a discussion of possible ‘blue corridors’ that would protect the studied species’ key migration routes and stocks, which are important for the fisheries, culture and nutrition of Pacific islanders.
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Yesson C, Letessier TB, Nimmo-Smith A, Hosegood P, Brierley AS, Hardouin M, Proud R. Improved bathymetry leads to >4000 new seamount predictions in the global ocean - but beware of phantom seamounts! UCL OPEN ENVIRONMENT 2021; 3:e030. [PMID: 37228795 PMCID: PMC10171409 DOI: 10.14324/111.444/ucloe.000030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 11/03/2021] [Indexed: 05/27/2023]
Abstract
Seamounts are important marine habitats that are hotspots of species diversity. Relatively shallow peaks, increased productivity and offshore locations make seamounts vulnerable to human impact and difficult to protect. Present estimates of seamount numbers vary from anywhere between 10,000 to more than 60,000. Seamount locations can be estimated by extracting large, cone-like features from bathymetry grids (based on criteria of size and shape). These predicted seamounts are a useful reference for marine researchers and can help direct exploratory surveys. However, these predictions are dependent on the quality of the surveys underpinning the bathymetry. Historically, quality has been patchy, but is improving as mapping efforts step up towards the target of complete seabed coverage by 2030. This study presents an update of seamount predictions based on SRTM30 PLUS global bathymetry version 11 and examines a potential source of error in these predictions. This update was prompted by a seamount survey in the British Indian Ocean Territory in 2016, where locations of two putative seamounts were visited. These 'seamounts' were targeted based on previous predictions, but these features were not detected during echosounder surveys. An examination of UK hydrographic office navigational (Admiralty) charts for the area showed that the summits of these putative features had soundings reporting 'no bottom detected at this depth' where 'this depth' was similar to the seabed reported from the bathymetry grids: we suspect that these features likely resulted from an initial misreading of the charts. We show that 15 'phantom seamount' features, derived from a misinterpretation of no bottom sounding data, persist in current global bathymetry grids and updated seamount predictions. Overall, we predict 37,889 seamounts, an increase of 4437 from the previous predictions derived from an older global bathymetry grid (SRTM30 PLUS v6). This increase is due to greater detail in newer bathymetry grids as acoustic mapping of the seabed expands. The new seamount predictions are available at https://doi.pangaea.de/10.1594/PANGAEA.921688.
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Affiliation(s)
- Chris Yesson
- Institute of Zoology, Zoological Society of London, Regent’s Park, London NW1 4RY, UK
| | - Tom B. Letessier
- Institute of Zoology, Zoological Society of London, Regent’s Park, London NW1 4RY, UK
| | - Alex Nimmo-Smith
- School of Biological & Marine Science, University of Plymouth, Plymouth, Devon PL4 8AA, UK
| | - Phil Hosegood
- School of Biological & Marine Science, University of Plymouth, Plymouth, Devon PL4 8AA, UK
| | - Andrew S. Brierley
- Pelagic Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TS, UK
| | - Marie Hardouin
- Institute of Zoology, Zoological Society of London, Regent’s Park, London NW1 4RY, UK
- Imperial College London, Silwood Park, Ascot, Berkshire SL5 7PY, UK
| | - Roland Proud
- Pelagic Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TS, UK
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Estimating Pelagic Fish Biomass in a Tropical Seascape Using Echosounding and Baited Stereo-Videography. Ecosystems 2021. [DOI: 10.1007/s10021-021-00723-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Cambra M, Lara-Lizardi F, Peñaherrera-Palma C, Hearn A, Ketchum JT, Zarate P, Chacón C, Suárez-Moncada J, Herrera E, Espinoza M. A first assessment of the distribution and abundance of large pelagic species at Cocos Ridge seamounts (Eastern Tropical Pacific) using drifting pelagic baited remote cameras. PLoS One 2021; 16:e0244343. [PMID: 34793440 PMCID: PMC8601560 DOI: 10.1371/journal.pone.0244343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 10/11/2021] [Indexed: 11/18/2022] Open
Abstract
Understanding the link between seamounts and large pelagic species (LPS) may provide important insights for the conservation of these species in open water ecosystems. The seamounts along the Cocos Ridge in the Eastern Tropical Pacific (ETP) ocean are thought to be ecologically important aggregation sites for LPS when moving between Cocos Island (Costa Rica) and Galapagos Islands (Ecuador). However, to date, research efforts to quantify the abundance and distribution patterns of LPS beyond the borders of these two oceanic Marine Protected Areas (MPAs) have been limited. This study used drifting-pelagic baited remote underwater video stations (BRUVS) to investigate the distribution and relative abundance of LPS at Cocos Ridge seamounts. Our drifting-pelagic BRUVS recorded a total of 21 species including elasmobranchs, small and large teleosts, dolphins and one sea turtle; of which four species are currently threatened. Depth of seamount summit was the most significant driver for LPS richness and abundance which were significantly higher at shallow seamounts (< 400 m) compared to deeper ones (> 400m). Distance to nearest MPA was also a significant predictor for LPS abundance, which increased at increasing distances from the nearest MPA. Our results suggest that the Cocos Ridge seamounts, specifically Paramount and West Cocos which had the highest LPS richness and abundance, are important aggregation sites for LPS in the ETP. However, further research is still needed to demonstrate a positive association between LPS and Cocos Ridge seamounts. Our findings showed that drifting pelagic BRUVS are an effective tool to survey LPS in fully pelagic ecosystems of the ETP. This study represents the first step towards the standardization of this technique throughout the region.
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Affiliation(s)
- Marta Cambra
- Programa de Posgrado en Biología, Universidad de Costa Rica, San Pedro, San José, Costa Rica
- Centro de Investigación en Ciencias del Mar y Limnología, Universidad de Costa Rica, San Pedro, San José, Costa Rica
| | - Frida Lara-Lizardi
- MigraMar, Sir Francis Drake Boulevard, Olema, California, United States of America
- Pelagios Kakunjá, La Paz, Baja California Sur, México
| | | | - Alex Hearn
- MigraMar, Sir Francis Drake Boulevard, Olema, California, United States of America
- Galapagos Science Center, Universidad San Francisco de Quito, Quito, Ecuador
| | - James T. Ketchum
- MigraMar, Sir Francis Drake Boulevard, Olema, California, United States of America
- Pelagios Kakunjá, La Paz, Baja California Sur, México
- Centro de Investigaciones Biológicas del Noroeste-CIBNOR, La Paz, Baja California Sur, México
| | - Patricia Zarate
- MigraMar, Sir Francis Drake Boulevard, Olema, California, United States of America
- División de Investigación Pesquera, Instituto de Fomento Pesquero, Valparaíso, Chile
| | - Carlos Chacón
- Fundación Pacífico, Sabana Norte, San José, Costa Rica
| | | | | | - Mario Espinoza
- Centro de Investigación en Ciencias del Mar y Limnología, Universidad de Costa Rica, San Pedro, San José, Costa Rica
- MigraMar, Sir Francis Drake Boulevard, Olema, California, United States of America
- Escuela de Biología, Universidad de Costa Rica, San Pedro, San José, Costa Rica
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Schwarz JN. Dynamic partitioning of tropical Indian Ocean surface waters using ocean colour data - management and modelling applications. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 276:111308. [PMID: 32891983 DOI: 10.1016/j.jenvman.2020.111308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/16/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Over the past few decades, partitioning of the surface ocean into ecologically-meaningful spatial domains has been approached using a range of data types, with the aim of improving our understanding of open ocean processes, supporting marine management decisions and constraining coupled ocean-biogeochemical models. The simplest partitioning method, which could provide low-latency information for managers at low cost, remains a purely optical classification based on ocean colour remote sensing. The question is whether such a simple approach has value. Here, the efficacy of optical classifications in constraining physical variables that modulate the epipelagic environment is tested for the tropical Indian Ocean, with a focus on the Chagos marine protected area (MPA). Using remote sensing data, it was found that optical classes corresponded to distinctive ranges of wind speed, wind stress curl, sea surface temperature, sea surface slope, sea surface height anomaly and geostrophic currents (Kruskal-Wallis and post-hoc Tukey honestly significantly different tests, α = 0.01). Between-class differences were significant for a set of sub-domains that resolved zonal and meridional gradients across the MPA and Seychelles-Chagos Thermocline Ridge, whereas between-domain differences were only significant for the north-south gradient (PERMANOVA, α = 0.01). A preliminary test of between-class differences in surface CO2 concentrations from the Orbiting Carbon Observatory-2 demonstrated a small decrease in mean pCO2 with increasing chlorophyll (chl), from 418 to 398 ppm. Simple optical class maps therefore provide an overview of growth conditions, the spatial distribution of resources - from which habitat fragmentation metrics can be calculated, and carbon sequestration potential. Within the 17 year study period, biotic variables were found to have decreased at up to 0.025%a-1 for all optical classes, which is slower than reported elsewhere (Mann-Kendall-Sen regression, α = 0.01). Within the MPA, positive Indian Ocean Dipole conditions and negative Southern Oscillation Indices were weakly associated with decreasing chl, fluorescence line height (FLH), eddy kinetic energy, easterly wind stress and wind stress curl, and with increasing FLH/chl, sea surface temperature, SSH gradients and northerly wind stress, consistent with reduced surface mixing and increased stratification. The optical partitioning scheme described here can be applied in Google Earth Engine to support management decisions at daily or monthly scales, and potential applications are discussed.
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Affiliation(s)
- Jill N Schwarz
- School of Biological & Marine Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK.
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Perez‐Correa J, Carr P, Meeuwig JJ, Koldewey HJ, Letessier TB. Climate oscillation and the invasion of alien species influence the oceanic distribution of seabirds. Ecol Evol 2020; 10:9339-9357. [PMID: 32953065 PMCID: PMC7487247 DOI: 10.1002/ece3.6621] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/30/2020] [Accepted: 07/09/2020] [Indexed: 12/29/2022] Open
Abstract
Spatial and temporal distribution of seabird transiting and foraging at sea is an important consideration for marine conservation planning. Using at-sea observations of seabirds (n = 317), collected during the breeding season from 2012 to 2016, we built boosted regression tree (BRT) models to identify relationships between numerically dominant seabird species (red-footed booby, brown noddy, white tern, and wedge-tailed shearwater), geomorphology, oceanographic variability, and climate oscillation in the Chagos Archipelago. We documented positive relationships between red-footed booby and wedge-tailed shearwater abundance with the strength in the Indian Ocean Dipole, as represented by the Dipole Mode Index (6.7% and 23.7% contribution, respectively). The abundance of red-footed boobies, brown noddies, and white terns declined abruptly with greater distance to island (17.6%, 34.1%, and 41.1% contribution, respectively). We further quantified the effects of proximity to rat-free and rat-invaded islands on seabird distribution at sea and identified breaking point distribution thresholds. We detected areas of increased abundance at sea and habitat use-age under a scenario where rats are eradicated from invaded nearby islands and recolonized by seabirds. Following rat eradication, abundance at sea of red-footed booby, brown noddy, and white terns increased by 14%, 17%, and 3%, respectively, with no important increase detected for shearwaters. Our results have implication for seabird conservation and island restoration. Climate oscillations may cause shifts in seabird distribution, possibly through changes in regional productivity and prey distribution. Invasive species eradications and subsequent island recolonization can lead to greater access for seabirds to areas at sea, due to increased foraging or transiting through, potentially leading to distribution gains and increased competition. Our approach predicting distribution after successful eradications enables anticipatory threat mitigation in these areas, minimizing competition between colonies and thereby maximizing the risk of success and the conservation impact of eradication programs.
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Affiliation(s)
- Julian Perez‐Correa
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Escuela de Ciencias AmbientalesFacultad de IngenieríaUniversidad Espíritu SantoSamborondónEcuador
- Imperial College LondonLondonUK
| | - Peter Carr
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
| | - Jessica J. Meeuwig
- Centre for Marine Futures, Oceans Institute and School of Animal BiologyThe University of Western AustraliaCrawleyWAAustralia
| | - Heather J. Koldewey
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
- Conservation and PolicyZoological Society of LondonLondonUK
| | - Tom B. Letessier
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Centre for Marine Futures, Oceans Institute and School of Animal BiologyThe University of Western AustraliaCrawleyWAAustralia
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Thorngren L, Dunér Holthuis T, Lindegarth S, Lindegarth M. Developing methods for assessing abundance and distribution of European oysters (Ostrea edulis) using towed video. PLoS One 2017; 12:e0187870. [PMID: 29141028 PMCID: PMC5687756 DOI: 10.1371/journal.pone.0187870] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 10/29/2017] [Indexed: 11/18/2022] Open
Abstract
Due to large-scale habitat losses and increasing pressures, benthic habitats in general, and perhaps oyster beds in particular, are commonly in decline and severely threatened on regional and global scales. Appropriate and cost-efficient methods for mapping and monitoring of the distribution, abundance and quality of remaining oyster populations are fundamental for sustainable management and conservation of these habitats and their associated values. Towed video has emerged as a promising method for surveying benthic communities in a both non-destructive and cost-efficient way. Here we examine its use as a tool for quantification and monitoring of oyster populations by (i) analysing how well abundances can be estimated and how living Ostrea edulis individuals can be distinguished from dead ones, (ii) estimating the variability within and among observers as well as the spatial variability at a number of scales, and finally (iii) evaluating the precision of estimated abundances under different scenarios for monitoring. Overall, the results show that the can be used to quantify abundance and occurrence of Ostrea edulis in heterogeneous environments. There was a strong correlation between abundances determined in the field and abundances estimated by video-analyses (r2 = 0.93), even though video analyses underestimated the total abundance of living oysters by 20%. Additionally, the method was largely repeatable within and among observers and revealed no evident bias in identification of living and dead oysters. We also concluded that the spatial variability was an order of magnitude larger than that due to observer errors. Subsequent modelling of precision showed that the total area sampled was the main determinant of precision and provided general method for determining precision. This study provides a thorough validation of the application of towed video on quantitative estimations of live oysters. The results suggest that the method can indeed be very useful for this purpose and we therefor recommend it for future monitoring of oysters and other threatened habitats and species.
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Affiliation(s)
- Linnea Thorngren
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- * E-mail:
| | | | - Susanne Lindegarth
- Department of Marine Sciences–Tjärnö, University of Gothenburg, Strömstad, Sweden
| | - Mats Lindegarth
- Department of Marine Sciences–Tjärnö, University of Gothenburg, Strömstad, Sweden
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